htpdate is a command line tool that allows you to synchronize the date and time on your local machine with that of a remote web server. It does this by connecting to a specified web server and using the date and time information provided in the HTTP headers to update the system clock on your local machine.
The idea behind htpdate is that many web servers are configured to provide accurate date and time information in the HTTP headers, so by connecting to one of these servers and using the information provided, you can ensure that your local machine has the correct date and time.
It’s worth noting that htpdate is not the most accurate way of synchronizing time, because the time on the web server can be affected by network latency and other factors.
Other tools like NTP (Network Time Protocol) are more accurate and robust, but may require additional setup and configuration. htpdate is a good choice for quickly synchronizing time on a machine, especially for machines that do not have access to a NTP server.
If you encounter the below error while running the command htpdate:
htpdate: command not found
you may try installing the below package as per your choice of distribution:
| Distribution | Command |
|---|---|
| Debian | apt-get install htpdate |
| Ubuntu | apt-get install htpdate |
| Kali Linux | apt-get install htpdate |
| OS X | brew install htpdate |
| Raspbian | apt-get install htpdate |
htpdate Command Examples
1. Synchronize date and time:
# sudo htpdate host
2. Perform simulation of synchronization, without any action:
# htpdate -q host
3. Compensate the systematic clock drift:
# sudo htpdate -x host
4. Set time immediate after the synchronization:
# sudo htpdate -s host